C-Arm Radiation Safety in Practice: Hazards and ALARA

Is C-arm radiation harmful?

The beam is ionising radiation, so there is a theoretical risk at any dose and a clear risk at high cumulative doses. Fluoroscopy is the usual cause of exposure because it runs continuously, unlike a single radiograph. Typical hazards for staff are cumulative dose to the hands, the eye lens and the thyroid, and for patients skin dose during long procedures.

Radiation protection works on the principle of ALARA, as low as reasonably achievable. The aim is not zero use, because the image guidance usually reduces other risks, but disciplined use only when the image is needed.

Time, distance and shielding

Time: shorten fluoroscopy by using intermittent pulses, last-image hold and by thinking before pressing the pedal. Distance: scatter falls quickly with distance, roughly following the inverse-square rule, so one step back makes a real difference. Shielding: lead aprons, thyroid collars, leaded glasses, mobile shields and table-side curtains. Our article on safe distance from a C-arm shows how scatter spreads around the table.

Protective garments only work if they fit, are stored hanging and are inspected regularly for cracks. More on equipment is in radiation protection equipment.

• Pulse the beam; avoid continuous exposure
• Step back from the table whenever you can
• Wear apron, thyroid collar and leaded glasses
• Use mobile shields and table curtains
• Wear dosimeters as required by the facility

Dose-saving features on the machine

Modern C-arms help the team. Pulsed fluoroscopy with adjustable frame rate, automatic kV and mA control, collimation, virtual collimators and last-image hold all reduce the dose. A laser localiser lets the operator centre the beam without taking an exposure, and a dose-area-product display makes dose visible during the case.

For example, the Arcovis DRF-C has six fluoroscopy modes selectable from the foot pedal and a dual laser localiser, and Perlove offers models with remote exposure and laser positioning on both tube and flat panel. Check the exact feature list for the model you buy, because options differ.

Positioning that reduces scatter

Position the tube below the table and the detector above, so that scatter is directed away from the operator's upper body. Place the detector as close to the patient as practical and keep the patient close to the detector, which reduces both dose and image blur. Use the smallest field that covers the anatomy of interest.

The person who stays closest to the beam is usually the surgeon, so agree before the case who stands where. Anyone who does not need to be in the room during exposure should step out or stand behind a shield.

Common mistakes that raise exposure

The most frequent errors are simple: holding the pedal while thinking, running continuous mode for a task that pulsed mode can cover, leaving the tube above the table and standing next to the beam while waiting. Hands in the primary beam are another classic problem, especially during guide-wire or K-wire work; use instruments or a longer grip instead.

Teams also forget to check the garments. A cracked apron or a missing thyroid collar gives a false sense of safety. Make protective equipment checks part of the monthly routine and record the results. Use the machine's dose display as a teaching tool after the case, not only as a record.

Training, monitoring and regulation

Everyone who presses the pedal should be trained in basic radiation protection and in the specific machine. Personal dosimeters are normally worn under the apron at chest level, and a second one at collar level can be required for staff with high workloads. Review the readings regularly and investigate anomalies.

In the UAE, radiation sources and practitioners are subject to federal and local requirements, with facility licensing by DHA, DOH or MOHAP depending on the emirate. Confirm current rules with your radiation safety officer. Beckfinity's team can also advise on quality control and service planning through the maintenance service.